Exo is a totally original design. Any font family will resemble others because, in the end, the letter “a” should look like the letter “a.” There are thousands of typefaces so it is easy for one “a” to look similar to some other “a” without being a copy. If you apply this sort of criterion to fonts from your favourite foundries, you will have to say that a lot of them are copies.
When I didn’t know that much about typography, almost all fonts looked the same to me. But as I started to getting involved in type design, I found out that it wasn’t like that, that there are details which each give an overall look to a font - even though most people can’t consciously perceive the difference, they feel the difference, and so the details are very important.